Monthly Hell
by Sketchy-d00d
Summary: Every girl goes through it. So when Stile Stilinski was turned into a girl by a monster they were hunting it wa the last thing on his mind. Until it hit him like a sack of bricks. Sterek. Fem!PMSing!Stiles Worried!Caring!Derek (First Teen Wolf fanfic. Whoop! Whoop!)


**Sum: Every girl goes through it. So when Stile Stilinski was turned into a girl by a monster they were hunting it wa the last thing on his mind. Until it hit him like a sack of bricks. Sterek. Fem!PMSing!Stiles Worried!Caring!Derek**

 ** _Inspired by my own experiences this morning. I skipped church because of it._**

* * *

"You're bleeding," were the first words Derek said when he climbed through Stiles's window. It had only been a month since he had been turned into a _she_.

"No shit, Sherlock," Stiles groaned into her pillow and raised one hand, her middle finger sticking up for all to see. Derek smirked.

"You know we promised your dad we wouldn't."

"Better yet, go fuck yourself," Stiles moaned. She turned over so Derek could see her face. Her cheeks were a splotchy pink as if they didn't know whether to be a pale white or a dark red. She wore a pained expression and just looked utterly miserable.

Derek sobered up. All amusement gone from his expression, replaced instead with a very serious and very worried look. "You look like death reincarnated-"

"Well thanks," Stiles growled, nearly enough to shame any werewolf in Beacon Hills. "Go dig me a while and lay me in it."

"Why?"

"Because I'm dying." Stiles stated mater-of-factly. She turned over to press her face into the pillow again, whimpering just slightly before curling into a ball.

Then the scent reached Derek's nose. The spicy scent of hormones that made him understand the situation. "Don't be so dramatic," Derek said, sitting on the edge of the bed and reaching over to rub the small of Stiles's back.

"'Don't be dramatic?'" Stiles repeated, shooting Derek a death glare that definitely shamed any Derek had sent her–him–before they were dating. "My uterus is literally tearing itself apart and the only thing you can say is 'don't be so dramatic?' You're the worst boyfriend ev–hey! What are you doing? Get back here!"

But Derek was gone. The curtains fluttering slightly in his wake as the only sign he'd even been there.

::V::

"Scott!" Derek breathed, jumping through the open window. Scott had seemingly got over his friends–especially the Pack–preferring to use the window rather than the front door. "I need your help."

"With what?" Scott asked, closing the book he had been reading.

"Stiles."

Scott raise an eyebrow in attempts to coax more out of Derek. "What about him? Her... That'll take some getting used to..."

Derek explained to Scott, his forest green eyes wide. "What do I do?"

Scott smirked. He started laughing when Derek just gave him a confused puppy look. "Sorry, I just find it funny that my best friend is having that time of month and you have to ask for help. Dude, just buy Stiles chocolate, make sure h-she takes a hot bath, and curl up with her after the bath. That's what I have to do for Allison."

Derek nodded and was gone before Scott could say anything else.

::V:V::

"I hate you," Stiles said when Derek kept through her window again. Derek offered her a box of chocolate and Stiles took it, raising an eyebrow and popping one of the dark chocolate squares into her mouth.

Derek disappeared into the bathroom and reappeared a few minutes later. "Get up."

"Why?"

"Get up," Derek repeated. He inched closer to Stiles's bed.

"Go away, I'm not getting up for anything."

"Yes you are."

"No I'm not. Why would I do that?" Stiles snapped, crossing her arms over her–admittedly more formed–chest. Derek took the last steps to the side of her bed. "What are you—hey! Put me down!"

"I'm running a bath for you," Derek replied, taking Stiles into the bathroom and sitting her on the toilet. Her short hair was sticking up wildly, a tell tale sign that she hadn't gotten out of bed at all that morning.

"I really hate you."

"No you don't, that's just your hormones speaking." Derek left and returned with a change of clothes. He was leaving the room when Stiles spoke again.

"You aren't joining me?"

Derek's inner wolf growled in agreement, wanting nothing more than to turn around and join Stiles. He wouldn't let himself though. He shook his head, his wolf whimpering in protest. "No, Stiles. I'm not joining you."

Stiles pouted and crossed her arms. "Jerk."

Derek ignored her. "When you finish your bath go back to bed."

Stiles watched as Derek left the room and scowled. He really was a jerk.

::V:V:V::

Stiles reluctantly got out of the water when it started to chill and her fingers pruned. She frowned at herself in the mirror and troweled herself dry.

She started to dress, being sure to protect the bikini type underwear that Erica had excitedly took her shopping for. She hadn't understood how girls wore them before but in all actuality they were comfortable and–to quote Erica–had a 'Hug-Your-Ass-Fit.' Stiles could've gone without that last part but supposed that it couldn't be helped.

She would have much preferred boy shorts, as Erica had called them, but the female werewolf had been adamant on the bikinis. She's also insisted that she get matching bras. Stiles stared at the plain whit bra that Derek had given her to change into.

It was the one she had insisted on getting, despite Erica's complaining that it didn't match anything. Then to make it up to Erica she'd let the she-wolf paint her nails.

She smiled, remembering Derek's expression when he'd walked through the closed bedroom door. The window had been locked while they'd been shopping and Stiles hadn't had a chance to reopen it.

Stiles glanced at the nails after strapping the bra. There were still flakes of green polish here and there. With a sigh she put the sweat pants on and held up the shirt.

It was too big to be one of her own and she hadn't changed much size wise when she'd become a she. Maybe it was one of her dad's, though why Derek would give her one of her dad's shirts she didn't know. She shrugged and put it on.

It was loose fitting and she relished that for a moment before leaving the bathroom, the sound of the water draining from the tub filtering into her room. She looked around, not finding Derek anywhere.

She scowled and popped another chocolate in her mouth. "Derek?"

A head of black hair lifted up from under the quilts on her bed, causing her to let out a stifled yelp. She grabbed the closest thing to her–an empty water bottle–and held it up in an attempt to be threatening.

Upon noticing it was just Derek she sighed before chucking the bottle at his head. He caught it easily. "Don't do that!" Stiles hissed, crossing her arms over her chest. "You almost gave me a heart attack."

Derek had the audacity to look sheepish, which only proved to make stiles slightly more upset. "Come here," he said, lifting an arm so Stiles could climb under the blankets.

Stiles sniffed before obliging, curling flush against Derek's chest and relinquishing her anger in his warmth. Derek curled his arms around her and she smiled. "You're just a big teddy bear," she chuckled.

Derek rolled his eyes, though Stiles couldn't see it, and replied. "And you're still as annoying as when we first started dating three months ago."

Stiles pinched his arm before closing her eyes in contentment. "Whatever."

"I'm glad you're wearing my shirt."

Stiles flushed.

::V:V:V:V::

It took them a few weeks more before they could turn Stiles into himself again. As soon as he was himself he turned to Derek with a serious expression.

"I am never ever underestimating a cranky female. And I understand their pain." He shivered and wrapped his arms around Derek. "I'm glad to be back in my own skin."

"I'm glad you're back too," Derek said, smiling slightly.


End file.
